Abstract:
A field emission device of simple structure enables stabilization and control of field emission current. A three-dimensional emitter formed on a base member incorporates therein a source layer on the side in contact with the base member, a drain layer on the side of the distal end including a tip and a channel region layer between the source layer and the drain layer. A gate is formed near the emitter. A strong electric field generated by applying a voltage to the gate causes cold electrons to be emitted from the emitter tip and the voltage applied to the gate also controls the conductivity of the channel region layer, whereby the field emission current emitted from the tip of the emitter is stabilized and controlled.
Abstract:
By providing a semiconductor device such as a cold cathode (7) with extra zener or avalanche structures (26, 27 and 32, 33, respectively) a robust structure is obtained which is resistant to damage during manufacture and use of a vacuum tube. The semiconductor zones (26, 27, 32, 33) are thus also utilized for realizing electron optics (particle optics).
Abstract:
A heterostructure electron emitter including a substrate having a surface with a predetermined potential barrier and a quantum well formed in the substrate adjacent the surface. Contacts are positioned on the substrate for coupling free electrons to the substrate and into the quantum well. An acoustic wave device is positioned on the substrate so as to direct acoustic waves to strike the free electrons in the quantum well and excite the free electrons sufficiently to cause the free electrons to overcome the potential barrier and to be emitted from the surface of the substrate.
Abstract:
An electron beam apparatus for applying an electron beam from an electron source onto a target plane is characterized by comprising one sheet of electrode disposed between said electron source for emitting the electron beam in parallel or substantially parallel and a target arrangement position, and a power source for supplying a desired voltage to said electrode.
Abstract:
A cold cathode device wherein a cold cathode and an anode face each other with an electron transit path intermediated therebetween, and one or more control electrodes structurally insulated from the said cathode and the anode, are provided exposing to the electron transit path. A cold cathode vacuum tube has an electron emission element having a p-type semiconductor region on an electron emission side and a work function lowering region with junctional relation to the p-type semiconductor region; and a plate electrode structurally insulated from the electron emission element by using an insulation layer which is formed with an electron transmit path corresponding in position to an electron emission area of the electron emission element.
Abstract:
A device for the multiplication of charge carriers of a given type by an avalanche phenomenon includes:a semiconductor material of homogeneous composition, placed in an electrical field.Perpendicular to the working field, plane and parallel layers which are thin as compared with the thickness of the material separating them, are made in this material and are n-doped or p-doped depending on the type of charge carrier, the said layers forming reservoirs where charge carriers of the said type are confined. The injection of at least one charge carrier of the said type in the charge carrier multiplying device sets off the multiplication of charge carriers through a process of impact ionization. This charge carrier is accelerated by the working field and thus acquires energy sufficient to make it capable of ejecting a charge carrier of the said type from the doped layer. The charge carriers obtained are guided by the working field. This impact ionization process is repeated from one layer to the next, and thus constitutes an avalanche multiplication phenomenon. The device can be applied to photosensors, photocathodes and infrared viewing devices.
Abstract:
In order to improve the stability of a cold cathode (5) of the reverse biased junction type, a vacuum space (2) is coupled with a reservoir (10), within which a source (21) of material reducing the work function, for example caesium, is present. By influencing the vapor pressure and the temperature in component parts (13, 16) of the reservoir (10) and in the source (21), loss of caesium due to adsorption or other phenomena occurring at the emitting surface (8) of the cathode (5) can be compensated for by an incident flow of caesium (25).
Abstract:
A device for producing or amplifying coherent radiation includes a semiconductor device such as a laser. By means of electrons of high energy produced by a semiconductor cathode of the device, population inversion is obtained in an active layer of the laser structure. In this manner, laser action is obtained, which offers advantages, especially with II-VI materials which emit radiation of a wavelength shorter than the usual III-V materials, and which do not permit the desired population inversion to be obtained in the same manner as in III-V materials, by means of current injection across a pn junction. The semiconductor cathode and the laser structure can be arranged in mutual separation in a vacuum tube or be realized in one semiconductor body. The short-wave laser is especially advantageous for CD,DOR and VLP applications.
Abstract:
An electron emitting device including an active semiconductor layer having a surface from which electrons are emitted. The layer is doped with impurity atoms at a density which decreases with distance from the surface.
Abstract:
The invention relates to a semiconductor cathode based on avalanche breakdown in the p-n junction. The released electrons obtain extra accelerating energy by means of an electrode provided on the device. The achieved efficiency increase makes the manufacture of such cathodes in planar silicon technology sensible. Such cathodes are applied, for example, in cathode ray tube, flat displays, pick-up tubes and electron lithography.